<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>duogedivdanrudanchu </title>
	<style>
		div{
			width: 200px;
			height: 200px;
			background:red;
			filter:alpha(opacity:30);
			opacity: 0.3;
			float: left;
			margin: 20px;
		}
	</style>
	<script>
		window.onload=function ()
		{
			var aDiv = document.getElementsByTagName("div");
			for (var i = 0; i < aDiv.length; i++)
			{
				aDiv[i].alpha = 30;
				aDiv[i].onmouseover = function ()
				{
					startMove(this, 100)
				};
				aDiv[i].onmouseout = function ()
				{
					startMove(this, 30)
				}
			}
		};



			function startMove(obj, iTarget)
			{
				clearInterval(obj.timer);
				obj.timer = setInterval(function ()
				{
					var speed =(iTarget-obj.alpha)/6;
					speed = speed >0? Math.ceil(speed) : Math.floor(speed);
					if (obj.alpha == iTarget)
					{
						clearInterval(obj.timer);
					}
					else
						{
						obj.alpha += speed;
						obj.style.filter = "alpha(opacity:"+ obj.alpha +")";
						obj.style.opacity = obj.alpha / 100;
					}
				}, 30);

			}


	</script>
</head>
<body>
<div></div>
<div></div>
<div></div>
<div></div>

</body>
</html>